Sökning: "geometric distortions"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden geometric distortions.

  1. 1. Quality assurance for magnetic resonance imaging (MRI) in radiotherapy

    Detta är en avhandling från Umeå : Department of radiation sciences, Umeå university

    Författare :Mary Adjeiwaah; Tufve Nyholm; Rob HN Tijssen; [2017]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic resonance imaging; Radiotherapy; geometric distortions; patient-induced susceptibilities MR-only; radiofysik; radiation physics;

    Sammanfattning : Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. LÄS MER

  2. 2. Geometric Models for Rolling-shutter and Push-broom Sensors

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Erik Ringaby; Per-Erik Forssén; Tomáŝ Pajdla; [2014]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Almost all cell-phones and camcorders sold today are equipped with a  CMOS (Complementary Metal Oxide Semiconductor) image sensor and there is also a general trend to incorporate CMOS sensors in other types of cameras. The CMOS sensor has many advantages over the more conventional CCD (Charge-Coupled Device) sensor such as lower power consumption, cheaper manufacturing and the potential for onchip processing. LÄS MER

  3. 3. Geometric Computer Vision for Rolling-shutter and Push-broom Sensors

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Erik Ringaby; Per-Erik Forssén; Anders Heyden; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rolling shutter cmos video rectification stabilisation push-broom kinect;

    Sammanfattning : Almost all cell-phones and camcorders sold today are equipped with a CMOS (Complementary Metal Oxide Semiconductor) image sensor and there is also a general trend to incorporate CMOS sensors in other types of cameras. The sensor has many advantages over the more conventional CCD (Charge-Coupled Device) sensor such as lower power consumption, cheaper manufacturing and the potential for on-chip processing. LÄS MER

  4. 4. High-resolution diffusion-weighted brain MRI under motion

    Detta är en avhandling från Stockholm : Karolinska Institutet, Dept of Clinical Neuroscience

    Författare :Mathias Engström; Karolinska Institutet.; Karolinska Institutet.; [2014]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES;

    Sammanfattning : Magnetic resonance imaging is one of the fastest developing medical imaging techniques. It provides excellent soft tissue contrast and has been a leading tool for neuroradiology and neuroscience research over the last decades. One of the possible MR imaging contrasts is the ability to visualize diffusion processes. LÄS MER

  5. 5. Global Shape Description of Digital Objects

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Ola Weistrand; Christer Kiselman; Gunilla Borgefors; Örjan Smedby; Michael Floater; [2005]
    Nyckelord :Applied mathematics; shape description; shape approximation; surface parameterization; digital object; spherical harmonics; digital surface; digital image; Tillämpad matematik;

    Sammanfattning : New methods for global shape description of three-dimensional digital objects are presented. The shape of an object is first represented by a digital surface where the faces are either triangles or quadrilaterals. LÄS MER